I just got my new ys110, put on a 15-8 prop and put it in the test stand. I have a check valve between the return line an the tank and the tank line to the carb. The high speed adjust ment is recommended to be 1.5 turns out, but I want it rich for break in so I have it out about 2.5-3 turns. Low speed is out about 1.5-1.25 turns. it starts right up, prop is ballanced by the way. cool we are off...

wow sucks through the little tank in 4 minutes or less, no big deal, I just think we are running rich so no worries.

Question #1. After the first tank is almost done I turn it off, I notice the carb is now full of fuel about 30- second later, so I dont get it, the tank is pressurized, what releives the pressure when the engine is turned off??? nothing? does it just continue to shove fuel into the carb? the manual says not to touch the rugulator. I see 3 adjustments only, high speed , low speed, and the regulator that you are not to touch, factory set at FLUSH. SO is fuel suppose to just fill up the carb after running?

#2 after 4 tanks we are starting to run nice, but the engine quites, I know I am rich and I throttle up and killed it, but now even though I can turn it over by hand, the starter motor will not do it. Maybe my battery was getting weak, or maybe the engine rings are starting to seat and thus this motor will not turn it over.... not sure, I will figure this one out later.

Question #3 so after I am done I start to dissasemble the prop, I dont have my plane yet so I am not sure which aluminum spinner to buy, so I was using a plastic backplate and no spinner at all, just one of those lagre cap nuts that people used to use (maybe they still do), you know the one that you have to turn the starter rubber insert in backward to use to start the motor, well, I take off the prop and the plastic backplate is fused to the prop???? never seen this before, so I try to take it off, then hit it with and wrench, then try to pry it off with a screw driver, no way is this thing comming off, so I take pliers and I am trying to just get this thing off the prop, it is totally stuck, well the backplate breaks, and ten minites later this backplate is finally off the prop, in pieces, so anyone experience this before? I have only ran .46 and .61 2 strokes and have no experiance with 4 strokes at all, is this normal? is an aluminum spinner and backplate a must?

PLEASE HELP, I really appreciate it....

1) On some YS 4-strokes, fuel does drip into the carb after the engine is turned off. Most YS 4-strokes are mounted inverted, and if this is the case, then you get some fuel dripping out of the carb. This is not really a concern. You can reduce the chance of this happening by unplugging the pressure line to relieve tank pressure after shut down.

2) The piston rings started to seat and your starter battery was getting low.

3) That is not normal. I have seen that happening once, but not on a YS. I usually use spinners with aluminum backplate.

Don't use a plastic backplate spinner at all. It's bad enough to use a plastic spinner with a metal backplate. It would be better to use a name brand all aluminum spinner.

I've seen several Y-S's blow plastic spinners off the engine and once saw one that spread a aluminum one out to where the prop blades could spin underneath it.

So be fore warned.

Enjoy,

Jim

1: If you don't de-pressurize the fuel tank and leave the throttle wide open, the pressurization will pump fuel into the carb. You can solve this by unplugging the vent line, not the fuel line. If you unplug the fuel line the fule will squirt out all over the place.

2: If it is still to rich and you throttled up it will die. After 2 tanks in my 63 i had to lean it a full turn so it would run correctly. So if it quit when you ran it up to full throttle and you left it at full throttle and the intake valve was open, the pressurization will pump fuel into the cylinder, jamming it; even after a short period of time before restarting it. You have to open the exhaust valve and get all the fuel out of the cylinder and then you can start it again.

3: No clue.


I went through the same exact things with my YS 63. Before this i had also run only 46-61 2 strokes. I hope this helps, and i think it will. Don't hesitate to email me with anymore questions.

Wolfpack, #3 was caused by friction between the prop and the spinner back plate as everything slipped. The thing hits hard so make sure you have everything very tight and double nutted. Being able to run a plastic backplate is hit and miss at best. I think Jim says it best in his post, don't even try it at all.

Ed M.

1. The carb should not fill with the motor turned off regardless of the tank pressure. This is caused from several things. First, at three turns out you are richer than needed ven for break-in. Two, possibly a bad seating of the gasket in the regulator. Three, the regulator might need to be turned in a little bit. Do not be afraid of turning the regulator. Just remember what turns you make.

2. The motor is probably flooding at three turns out. Two turns is fine for break-in.

3. Use an aluminum spinner with all YS motors. Most plastic spinners will give way with a rather violent and potentially dangerous explosion.

You said that you also had a check valve between the tank and the carburetor?
You can take the check valve out and replace it with a filter. This probably won't correct any of your problems, but could cause a restriction in the fuel flow to the carburetor.
If had to take a guess at why the backplate stuck to the prop, I would have to say that when you leaned it out to get your maximum RPM, the engine got too lean, and instead of throwing the spinner off like it would do with an aluminum spinner, it just slipped and melted the backplate to the propeller.

Greg

QUOTE 1. The carb should not fill with the motor turned off regardless of the tank pressure. This is caused from several things. First, at three turns out you are richer than needed ven for break-in. Two, possibly a bad seating of the gasket in the regulator. Three, the regulator might need to be turned in a little bit. Do not be afraid of turning the regulator. Just remember what turns you make.

Then what would cause it? Pressurization is what causes it, if you don't depressurize it then it will flood the carb. Even if there is a rich needle valve, what's pumping the fuel into the carb? That wouldn't be the pressurization would it? Well it is, and unplugging the pressure line, not the fuel line, after every run will depressurize the tank and you won't flood the carb with the fuel.

If the plunger in the regulator is not seating, it will let the carb fill with fuel. It is not normal for the carb to flood if the engine is off. I had a 63 drip on me and there was no trash under the plunger. I marked where the regulator screw was, turned the regulator in all the way then back out to where it originally was and the drip stopped. Still running perfectly 3 months later and no drips. I do release the pressure after each flight, but if I don't, it won't drip.

As for the original guy..it just sounds like he's trying to run his engine too rich. YS 4 strokes hate being too rich.

Thanks for the responses, one more question, I have a check valve in the pressure line form the carb to the tank, so during this test setup I cannot relieve the pressure by disconnecting the line at the engine since the check valve will come into play, so does everyone just put a tee in that line after the check valve and run that to a fuel dot and relieve pressure that way? just for clairification I am only runing a check valve here, I do not have anything between the tank and the carb intake. ys recommends a fuel filter in both lines, is that how everyone has it set up, per their instructions on the web?

thanks again everyone!

Yes, if you can't get to the pressure line to disconnect the line at the check valve and relieve the pressure, use a fuel dot between the check valve and tank. You need to pull the line off between the check valve and tank to let the pressure off....pulling it off at the engine won't do anything. Another fuel dot in the fuel line between the tank and engine will let you fuel without pulling that line off. I run a filter between the engine and check valve to keep anything from the engine from getting in the check valve, and a filter between the tank and engine to keep anything from the tank from getting into the engine.

Use a tee in the pressure line after the check valve to relieve pressure in the tank. I always use two tee's with all my YS 4-strokes, as can be seen in the picture below:



The red line is the pressure line and the blue line is the feed line. Note the fuel filter before the check valve on the pressure line and another fuel filter before the tee on the feed line. The line from each tee is run to a fuel dot:

Richard L,
Nice clean looking set-up. I like your fuel dots, what brand are they? It looks like they are black anodized.

Pilgrim

Pilgrim, those are [link=http://www.qualityrcproducts.com/prod_miraclefueler.html]"Miracle Fuelers"[/link] being sold by Madison Components. They come in aluminum finish also. I like these because they lock and unlock by twisting instead of pushing and pulling, which can be hard on the fingernails and the cowl.

awesome, thanks!!!!

by the way, when mounting the muffler do you bottom out the pipe into the engine and then lock it with the nut, does this ever viberate loose? My magnums 2 strokes always vibrated loose, and thus I used locking nuts. does the muffler itself ever vibrate loose from the threaded pipe as well? what do you do to keep this from happening?

My YS mufflers have yet to vibrate loose with the stock pipe and nut, and I don't use threadlocker. The weight of the muffler helps tighten itself to the pipe and nut. Just make sure everything is tight.

Ok one last question for now, I take the baffles out of my magnums, is it ok to take the baffles out of this ys 110? Will I get better performance with the ys baffle out? where I fly noise is not an issue...

no need to touch the muffler! It's designed to run its best just the way it is. YS motors have alot of torque and will eat plastic spinners. I think we all have learned this the hard way. I have a 14x8 apc with the plastic backplate fused to the prop(and the hole is now about halfway between the center and the edge!) still sitting on my bench from a few years ago as a reminder. The new Great Planes spinners with aluminum backplate works great!.
After the first tank you can go almost to the optimum settings on your needles(just a hair rich!). Otherwise you are doing nothing for the motor. Also after the last run of the day and you empty the tank, put the glow back on and run the motor dry! No need for afterun oil. Good luck!